Project F-250: How to Choose the Right Battery for Our Truck

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Update by Tom Suddard to the Ford F-250 project car
Apr 3, 2020

Put simply, our F-250 needed more power. No, not more horsepower—its V10 makes plenty of horsepower—but more electricity. A new battery is all it took to fix it. 

How to Test a Battery

Batteries are annoying, right? They work perfectly for four, five, six or more years, then one day they just stop and leave you stranded. 

Except, well, that’s not actually what’s going on. Batteries don’t just stop working one day. Instead, they gradually degrade until they don’t have enough power to start your engine. That familiar click-click-click of a dead battery means you’d been on borrowed time for months, with the battery just barely starting the engine as it continued to degrade. 

To combat this, we’re pretty vigilant about testing our batteries on a regular schedule. We picked up a resistive battery tester (colloquially known as a hand toaster) for about $20 and annually use it on every battery in our fleet. 

Rather than just measure voltage like a multimeter, testers like these apply a load to the battery in order to measure the number of amps it can produce. This is a much more accurate way of measuring a battery’s condition than just testing its voltage, and it has meant that we very rarely find ourselves unexpectedly jump-starting a car despite owning a dozen of them. 

Unsurprisingly, the 10-plus-year-old battery that came in our truck failed the test, measuring weak. Could we have kept it for a few more months? Absolutely, but it’s way easier to replace a battery in the garage than it is in the middle of a road trip or a rainstorm. More than anything else, this truck needs to be reliable, and a worn-out battery doesn’t fit that plan.  

How to Choose a Battery

That left the question: What battery should we choose? Normally we’d head over to our local battery distributor and buy the least expensive wholesale group 65 battery on the shelf, but in this case we wanted something fancier: a dual-purpose battery that could handle the cranking load of starting our V10 as well as withstanding the deeper discharge cycles that come from leaving this truck parked for weeks at a time or running an inverter at the track. Bonus points for durable AGM construction, because we hate leaky batteries and don’t want to replace this again any time soon. 

So we called Optima, which recommended its Optima Yellowtop D34. This battery ticked all our boxes and included the necessary adapter to nicely slot into our F-250’s factory battery tray. Its $276.99 list price is about a hundred dollars more than a parts-store battery with an equivalent three-year warranty, but we’re willing to see if the Optima really holds up to its claim of delivering three times the life of a conventional battery.

Are we leaving capacity on the table by choosing a battery that’s not actually the factory group 65 form factor? We’ll let the numbers tell the tale: The Interstate battery that we removed from the truck is rated at 850 cold cranking amps (starting power) and 150 minutes of reserve capacity (the amount of time a fully-charged battery at 80 degrees can produce 25 amps at a minimum of 10.5 volts). 

The Optima, in comparison, is rated at 750 cold cranking amps and 120 minutes of reserve capacity. So, we’re switching to a less powerful battery that promises to be more durable. Will it pay off? Only time will tell. We did weigh both batteries, and surprisingly the Optima was heavier, clocking in at 44 pounds, 1 ounce, where the Interstate weighs 43 pounds, 5 ounces.

How to Install a Battery

Unfortunately, we experienced the downside of a traditional flooded battery as soon as we removed the old one: They can leak battery acid, and ours had done a number on our truck’s battery tray. 

Before installing the Optima, we unbolted the tray and coated it in POR-15 rust-converting paint so it wouldn’t get any worse. Fortunately, it was the only part of the truck affected; the sheet metal underneath still looked pristine. 

After the paint dried, we bolted the tray back in place, popped in the Optima, and went for a drive. The truck cranked faster than it ever had, proving our old battery had indeed been weak. 

With our truck back in action, we penciled the date of the battery installation into our calendar and parked the battery tester on the shelf. We’ll keep testing over the coming years and report back with our results.


Extra credit: For help on choosing a battery—and keeping that battery happy and healthy—we present Battery Saver’s Frank Gabrielli. 



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View comments on the GRM forums
purplepeopleeater Reader
4/2/20 2:40 p.m.

Be advised that should your Optima need to be recharged it is a more complicated procedure than just plugging in your charger & turning it on. Several years back I worked at a FLAPS that sold Optimas & we could never get them to take a charge when they came in flat. We were all idiots but that wasn't the reason. IIRC, it has been a while it needs to be charged in series through a conventional battery but if you have a flat Optima go to their website.


Ha! I threw away a battery from my challenge CRX because I couldn't get it to charge. @purplepeopleeater is correct-you can fool a regular charger into charging an AGM by using another battery, or by buying a specific charger.

bklecka New Reader
4/7/20 1:53 p.m.

I have owned a SuperDuty pickup since 2002. I have gone though several sets of batteries. I bought a couple sets of Motorcraft batteries and decided to find something better. I researched the Optima yellow tops and decided to buy a set. Autozone only had one in stock and I needed them that day so they suggested that I try their new line of AGM batteries. I bought a pair of the new Duralast Platinum AGM batteries and I have had fantastic luck with them. I am on my second set now and will continue to replace all my batteries with them. Plus they sell for about $169 apiece and usually if you ask for a discount they give you 5 or 10 percent off at the register. 

bashr52 New Reader
4/8/20 8:09 a.m.

You may want to replace the battery cables while you are at it as well. Those bolt on style terminals usually just end up spelling trouble.

Tom Suddard
Tom Suddard GRM+ Memberand Director of Marketing & Digital Assets
4/14/21 2:55 p.m.

Time for the one-year update here: So far so good. I leave the truck sitting for 2-3 weeks at a time with zero prep or charging, and the Optima hasn't let me down yet.

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